1. Field of the Invention
The present invention relates to an opening and closing valve for high-pressure gas which is used as a passageway handling a high-pressure gas and opens and closes the passageway by causing a valve body and a valve seat to come into contact with or separate from each other.
2. Description of Related Art
In a system which handles a high-pressure gas such as a fuel cell or a compressed natural gas (CNG), an opening and closing valve is used for various valves such as a stop valve. The opening and closing valve which is used for such a purpose is required to have a high sealing performance (an isolating performance) between a valve body and a valve seat and have durability for long-term use. Accordingly, it is important to satisfy both requirements to a high level.
Therefore, as an opening and closing valve for high-pressure gas which satisfies such requirements, an opening and closing valve for high-pressure gas is proposed in which a contact surface in a valve body is formed in a conical shape, a contact surface in a valve seat is formed as a tapered shape accommodating the valve body side contact surface, one of the valve body and the valve seat is formed of metal, and the other thereof is formed of a resin (for example, see Japanese Patent No. 4330943).